The invention relates to a semiconductor device comprising a semiconductor body provided with one or more semiconductor elements having one or more contact regions provided with connection conductors, the semiconductor body being attached to a side of an insulating substrate which is provided, on said side, with a first conductor pattern to which the connection conductors are connected and which is electrically connected to a second conductor pattern, which is situated on the other side of the insulating substrate and provided with contact bumps. Such a device is compact, inexpensive and easy to manufacture, and it is employed, for example, in the field of telecommunications. The invention also relates to a method of manufacturing such a device.
Such a device is disclosed in United States patent specification U.S. Pat. No. 5,726,489, published on Mar. 10, 1998. In said document, a description is given of a device wherein an IC (=Integrated Circuit) is secured with its connection regions to a conductor pattern of an insulating film which is provided on the other side with a conductor pattern comprising contact bumps which are connected to the conductor pattern on the other side of the film.
A drawback of the known device resides in that it is less suitable for certain ICs, particularly ICs which must be calibrated after they have been manufactured. This requires features which render the device more expensive and less compact.
Therefore, it is an object of the invention to provide a device which is very suitable for ICs which must be calibrated and which is also compact and inexpensive.
To achieve this, a device of the type mentioned in the opening paragraph is characterized in accordance with the invention in that the device is provided with one or more fuses and with an electronic component, a property of which can be adapted by means of the fuses, which component forms part of the semiconductor body, and the fuses form part of one of the conductor patterns on the insulating substrate. The invention is based first of all on the recognition that the various customary calibrating methods, wherein calibration means are incorporated in the semiconductor body, such as PROMs (=Programmable Read Only Memory), fuses or Zener diodes by means of which an electronic component is adjusted, lead to the above-mentioned problem. These methods take up a part of the surface of the semiconductor body, as a result of which the device is less compact and less cheap. The use of PROMs has the additional drawback that the calibration must be carried out by the customer which, for this reason, must be supplied with (measuring) data. In addition, the use of PROMs requires special process steps rendering the production process of the IC more expensive. Said drawback is also attached to the use of Zener diodes or fuses. The invention is further based on the recognition that fuses can be readily provided in one of the conductor patterns of the insulating substrate. This does not make the device more expensive or less compact, and it does not have the above-mentioned further drawbacks of the known methods. In addition, the device in accordance with the invention has the advantage that adjusting the component can very suitably take place after the IC and the connection conductors have been surrounded by an insulating synthetic resin envelope. The reason for this being that melting of fuses may involve contamination of the IC. In addition, the calibration of a finished product is more reliable and hence more accurate.
In a preferred embodiment, the fuses form part of the second conductor pattern. As a result, viewed in projection, the fuses may be situated, on the one hand, at the location of the semiconductor body, enabling the device to be very compact. In addition, the fuses remain outside a possible synthetic resin envelope of the semiconductor body and the connection conductors. Preferably, the fuses comprise a conductor track provided with a constriction and situated between two contact bumps. By virtue thereof, melting of the fuse can take place in a simple manner, namely by being energized. In addition, this can be readily carried out in the test phase of the device by making use of the customary test equipment. The contact bumps can readily be used to electrically connect the fuse.
In a very important embodiment, the insulating substrate comprises an insulating foil. Apart from the fact that the device is very compact by virtue of the small thickness of the foil, the use of a foil also enables fuses to be employed having a very narrow conductor track, for example in the range from 5 to 50 xcexcm, which is a necessary condition for melting fuses using as little current and power as possible. A suitable thickness of the fuses ranges from 0.1 to 2 xcexcm. By virtue thereof, damage to the device caused by said melting of the fuses can be precluded. A suitable thickness of the foil lies in the range between 50 and 200 xcexcm. Preferably, the contact bumps are provided in the form of a two-dimensional matrix on the substrate. This enables a large number of fuses to be provided at a location that can be freely selected.
In a particularly suitable embodiment, the component comprises a number of sub-components which can be short-circuited by means of switches which are connected to a decoder circuit which is connected to the fuses by means of which a binary signal can be sent to the decoder circuit. The decoder circuit is used to convert the data coded by means of the fuses so as to control the switches of the component to be calibrated. The decoder circuit has two sets of inputs, i.e. the natural inputs of the fuses and signal inputs which can be controlled by a test apparatus. In a normal mode, the decoder reads the fuses, and in a test mode, it reads the signal inputs. The calibration procedure takes place, for example, as follows: the decoder is brought into the test mode and the component is controlled by the test apparatus. The setting of the decoder yielding an optimum result for the value of the component is stored as software information in the test apparatus. These values are subsequently used to program the fuses. Finally, the calibration is checked in the normal mode. The calibration setting is then read from the fuses. The result must correspond to the previously found result in the test mode.
Preferably, the semiconductor body is secured with its lower side to the insulating substrate, and the connection conductors comprise an electrically conductive wire connection. This has the advantage that the electric contacts between the IC and the conductor pattern on the, preferably flexible, substrate are better protected against damage than in the situation where, for example, the IC is secured with its active upper side directly to the substrate. The semiconductor body and the wire connections are preferably surrounded by an electrically insulating synthetic resin.
A method of manufacturing a semiconductor device wherein one or more semiconductor elements, provided with one or more contact regions provided with connection conductors, are formed in a semiconductor body, which semiconductor body is secured to a side of an insulating substrate which is provided, on said side, with a first conductor pattern to which the connection conductors are connected and which is electrically connected to a second conductor pattern which is situated on the other side of the insulating substrate and provided with contact bumps, characterized in that the device is provided with one or more fuses and with an electronic component, a property of which can be adapted by means of the fuses, the component is formed in the semiconductor body and the fuses are formed in one of the conductor patterns on the insulating substrate. Preferably, a foil is used for the insulating substrate, and the fuses are provided in the form of a conductor track having a constriction between two contact bumps.
These and other aspects of the invention will be apparent from and elucidated with reference to the embodiment(s) described hereinafter.